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drop table if exists t1,t2;
create table t1 (a int not null auto_increment, b int not null, primary key(a));
insert into t1 (b) values (2),(3),(5),(5),(5),(6),(7),(9);
select SQL_CALC_FOUND_ROWS * from t1;
a b
1 2
2 3
3 5
4 5
5 5
6 6
7 7
8 9
select found_rows();
found_rows()
8
select SQL_CALC_FOUND_ROWS * from t1 limit 1;
a b
1 2
select found_rows();
found_rows()
8
select SQL_BUFFER_RESULT SQL_CALC_FOUND_ROWS * from t1 limit 1;
a b
1 2
select found_rows();
found_rows()
8
select SQL_CALC_FOUND_ROWS * from t1 order by b desc limit 1;
a b
8 9
select found_rows();
found_rows()
8
select SQL_CALC_FOUND_ROWS distinct b from t1 limit 1;
b
2
select found_rows();
found_rows()
6
select SQL_CALC_FOUND_ROWS b,count(*) as c from t1 group by b order by c desc limit 1;
b c
5 3
select found_rows();
found_rows()
6
select SQL_CALC_FOUND_ROWS * from t1 left join t1 as t2 on (t1.b=t2.a) limit 2,1;
a b a b
3 5 5 5
select found_rows();
found_rows()
8
drop table t1;
create table t1 (a int not null primary key);
insert into t1 values (1),(2),(3),(4),(5);
select sql_calc_found_rows a from t1 where a in (1,2,3) order by a desc limit 0,2;
a
3
2
select FOUND_ROWS();
FOUND_ROWS()
3
select sql_calc_found_rows a from t1 where a in (1,2,3) order by a+2 desc limit 0,2;
a
3
2
select FOUND_ROWS();
FOUND_ROWS()
3
drop table t1;
CREATE TABLE t1 (
`id` smallint(5) unsigned NOT NULL auto_increment,
`kid` smallint(5) unsigned NOT NULL default '0',
PRIMARY KEY (`id`),
KEY `kid` (`kid`)
);
CREATE TABLE t2 (
id smallint(5) unsigned NOT NULL auto_increment,
name varchar(50) NOT NULL default '',
email varchar(50) NOT NULL default '',
PRIMARY KEY (id),
UNIQUE KEY e_n (email,name)
);
EXPLAIN SELECT SQL_CALC_FOUND_ROWS DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL LIMIT 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 system PRIMARY,kid NULL NULL NULL 0 Const row not found; Using temporary
1 SIMPLE t2 ALL NULL NULL NULL NULL 200
SELECT SQL_CALC_FOUND_ROWS DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL LIMIT 10;
email
email1
email2
email3
email4
email5
email6
email7
email8
email9
email10
SELECT FOUND_ROWS();
FOUND_ROWS()
200
SELECT SQL_CALC_FOUND_ROWS DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL order by email LIMIT 10;
email
email1
email10
email100
email101
email102
email103
email104
email105
email106
email107
SELECT FOUND_ROWS();
FOUND_ROWS()
200
SELECT DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL LIMIT 10;
email
email1
email2
email3
email4
email5
email6
email7
email8
email9
email10
SELECT DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL ORDER BY email LIMIT 10;
email
email1
email10
email100
email101
email102
email103
email104
email105
email106
email107
INSERT INTO `t1` (`id`, `kid`) VALUES ('0', '150');
SELECT SQL_CALC_FOUND_ROWS DISTINCT email FROM t2 LEFT JOIN t1 ON kid = t2.id WHERE t1.id IS NULL LIMIT 10;
email
email1
email2
email3
email4
email5
email6
email7
email8
email9
email10
SELECT FOUND_ROWS();
FOUND_ROWS()
199
drop table t1,t2;
CREATE TABLE `t1` (
`titre` char(80) NOT NULL default '',
`numeropost` mediumint(8) unsigned NOT NULL auto_increment,
`maxnumrep` int(10) unsigned NOT NULL default '0',
PRIMARY KEY (`numeropost`),
KEY `maxnumrep` (`maxnumrep`)
) ENGINE=MyISAM ROW_FORMAT=FIXED;
INSERT INTO t1 (titre,maxnumrep) VALUES
('test1','1'),('test2','2'),('test3','3');
SELECT SQL_CALC_FOUND_ROWS titre,numeropost,maxnumrep FROM t1 WHERE numeropost IN (1,2) ORDER BY maxnumrep DESC LIMIT 0, 1;
titre numeropost maxnumrep
test2 2 2
SELECT FOUND_ROWS();
FOUND_ROWS()
2
SELECT SQL_CALC_FOUND_ROWS 1 FROM (SELECT 1) as a LIMIT 0;
1
SELECT FOUND_ROWS();
FOUND_ROWS()
1
SELECT SQL_CALC_FOUND_ROWS * FROM t1 WHERE numeropost > 1 LIMIT 0;
titre numeropost maxnumrep
SELECT FOUND_ROWS();
FOUND_ROWS()
2
SELECT SQL_CALC_FOUND_ROWS * FROM t1 LIMIT 0;
titre numeropost maxnumrep
SELECT FOUND_ROWS();
FOUND_ROWS()
3
SELECT SQL_CALC_FOUND_ROWS * FROM t1 ORDER BY numeropost LIMIT 0;
titre numeropost maxnumrep
SELECT FOUND_ROWS();
FOUND_ROWS()
3
drop table t1;
create table t1 (id int, primary key (id));
insert into t1 values (1), (2), (3), (4), (5);
select SQL_CALC_FOUND_ROWS * from t1 where id > 3 limit 0, 1;
id
4
select FOUND_ROWS();
FOUND_ROWS()
2
select SQL_CALC_FOUND_ROWS * from t1 where id > 3 AND 1=2 limit 0, 1;
id
select FOUND_ROWS();
FOUND_ROWS()
0
select SQL_CALC_FOUND_ROWS * from t1 where id > 6 limit 0, 1;
id
select FOUND_ROWS();
FOUND_ROWS()
0
drop table t1;
CREATE TABLE t1 ( a int not null, b int not null, KEY ab(a,b) );
INSERT INTO t1 VALUES ( 47, 1 );
INSERT INTO t1 VALUES ( 70, 1 );
SELECT * FROM t1
WHERE
(
( b =1 AND a BETWEEN 14 AND 21 ) OR
( b =2 AND a BETWEEN 16 AND 18 ) OR
( b =3 AND a BETWEEN 15 AND 19 )
);
a b
DROP TABLE t1;
CREATE TABLE t1 ( a integer, u varchar(15), r integer, key uao_idx( r, a, u));
DELETE FROM t1
WHERE ( r = 1 AND a IN ( 1, 2 ) AND ( u = 'w' OR u LIKE 'w/%' ) )
OR ( r = 1 AND a IN ( 3 ) AND ( u = 'w/U' OR u LIKE 'w/U/%' ) )
OR ( r = 1 AND a IN ( 1, 2, 3 ) AND ( u = 'w' ) );
drop table t1;
CREATE TABLE t1 (a VARCHAR(16), UNIQUE(a));
INSERT INTO t1 VALUES ('1'), ('2'), ('3');
SELECT SQL_CALC_FOUND_ROWS * FROM t1 WHERE a = '2' LIMIT 0, 1;
a
2
SELECT FOUND_ROWS();
FOUND_ROWS()
1
DROP TABLE t1;
CREATE TABLE t1 (a INT);
INSERT INTO t1 VALUES (0), (0), (1), (2);
SELECT SQL_CALC_FOUND_ROWS * FROM t1 WHERE a = 0 GROUP BY a HAVING a > 10;
a
SELECT FOUND_ROWS();
FOUND_ROWS()
0
DROP TABLE t1;
SELECT 'foo';
foo
foo
SELECT FOUND_ROWS();
FOUND_ROWS()
1
SELECT SQL_CALC_FOUND_ROWS 'foo';
foo
foo
SELECT FOUND_ROWS();
FOUND_ROWS()
1
SELECT SQL_CALC_FOUND_ROWS 'foo' limit 0;
foo
SELECT FOUND_ROWS();
FOUND_ROWS()
1
SELECT FOUND_ROWS();
FOUND_ROWS()
1
SELECT SQL_CALC_FOUND_ROWS 'foo' UNION SELECT 'bar' LIMIT 0;
foo
SELECT FOUND_ROWS();
FOUND_ROWS()
2
CREATE TABLE t1 (a int, b int);
INSERT INTO t1 VALUES (1,2), (1,3), (1,4), (1,5);
SELECT SQL_CALC_FOUND_ROWS DISTINCT 'a' FROM t1 GROUP BY b LIMIT 2;
a
a
SELECT FOUND_ROWS();
FOUND_ROWS()
1
DROP TABLE t1;
create table t1 (f1 int primary key, f2 tinyint) engine=myisam;
insert t1 values (10,3),(11,2),(12,3);
create table t2 (f3 int primary key) engine=myisam;
insert t2 values (11),(12),(13);
select f1 from t1,t2 where f1=f3 and f2=3 order by f1;
f1
12
select found_rows();
found_rows()
1
drop table t1, t2;
create table t1 (a1 int auto_increment primary key, c1 int);
insert t1 (a1) values (null);
insert t1 (a1) select null from t1;
insert t1 (a1) select null from t1;
insert t1 (a1) select null from t1;
insert t1 (a1) select null from t1;
insert t1 (a1) select null from t1;
insert t1 (a1) select null from t1;
insert t1 (a1) select null from t1;
insert t1 (a1) select null from t1;
insert t1 (a1) select null from t1;
update t1 set c1=a1 % 2;
create table t2 (a2 int, b2 int, c2 char(16) default '', primary key (a2, b2));
insert t2 select a1, 1, 'ok' from t1;
insert t2 select a1, 2, 'ko' from t1;
insert t2 select a1, 3, 'ko' from t1;
insert t2 select a1, 4, 'ok' from t1;
insert t2 select a1, 5, 'ok' from t1;
select sql_calc_found_rows distinct a1,c2 from t1 join t2 on a2=a1
where a1 <= 256 and c1=0 and c2='ok' order by a1 desc limit 46;
select found_rows();
found_rows()
128
drop table t1, t2;
create table t1 (i1 int, v1 int, primary key(i1,v1));
insert into t1 values (1,1),(2,2),(3,3);
create table t2 (i2 int primary key, v2 int);
insert into t2 values (1,5),(2,5),(3,10);
select 1 as res from t1 left join t2 on i1 = i2 where v2 = 5 or v1 = 5 or v1 = 10 order by v1;
res
1
1
select sql_calc_found_rows 1 as res from t1 left join t2 on i1 = i2 where v2 = 5 or v1 = 5 or v1 = 10 order by v1 limit 1;
select found_rows() as count;
count
2
select sql_calc_found_rows 1 as res from t1 left join t2 on i1 = i2 where v2 = 5 order by v1 limit 1;
select found_rows() as count;
count
2
drop table t1, t2;
create table t1 (i int, v varchar(64), key (i));
select sql_calc_found_rows * from t1 where i = 0 order by v limit 59,2;
i v
0 foo
0 foo
select found_rows();
found_rows()
75
select sql_calc_found_rows * from t1 ignore index (i) where i = 0 order by v limit 59,2;
i v
0 foo
0 foo
select found_rows();
found_rows()
75
drop table t1;
create table t1(c1 int);
insert into t1 values(1),(2),(3),(4),(5);
select * from t1 order by c1 limit 2,1;
c1
3
select found_rows();
found_rows()
3
select sql_calc_found_rows * from t1 order by c1 limit 2,1;
c1
3
select found_rows();
found_rows()
5
drop table t1;
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